One of the challenges associated with the manufacture of wheeled vehicles, especially large wheeled vehicles such as semi-trailer trucks and tractors, is the manufacture and assembly of an axle assembly for the suspension system. Structurally, there is a need to transition from the strength and stability of the axle to the moving mechanical components of the wheels and other suspension system components. There is also a need, however, to minimize the weight of the axle assembly, the complexity of the various components comprising the axle assembly, and the cost to manufacture and assemble the suspension system. Oftentimes, strength and stiffness are achieved at the expense of weight, cost, and/or ease of assembly.
In many prior art suspension systems, the axle assembly includes a single, continuous axle beam interconnecting one king pin housing to another. In some instances, the axle beam may actually include the king pin housing, and the entire axle beam-king pin housing assembly may be formed as a single component. A single, continuous axle assembly is often heavy and unwieldy, thereby making integration of such an assembly into the suspension system a challenging proposition. Additionally, manufacturing of the axle assembly itself is often difficult and costly.
Alternatively, many current axle assemblies include several distinct components interconnected to form a link between king pin housings, or to connect the axle to a pivot arm or other subassembly. In particular, the axle assembly may include an axle which interfaces at either end with an axle connector. Typically, the axle connector fits around the outside of the axle and is welded, press fit, or otherwise mechanically fastened in place. The structural strength and integrity of such a system is limited. Forces at the axle connector-axle interface tend to induce stresses, such as peel stresses, along the interface lines between the two components. These induced stresses may force the axle to separate from the axle connector, leading to a premature mechanical failure of the axle assembly.
The above prior art does not efficiently reduce weight, cost and manufacturing complexity; it also does not improve strength and performance while simultaneously simplifying the steps to assemble the suspension systems of the large wheeled vehicles.